Detector elephants: gentle giants sniff out explosives
- Wits University
An African elephant detects dangerous TNT using its extraordinary sense of smell.
Shot in November 2015, this incredible footage shows Chishuru, a 17-year-old male bull, carefully checking a row of white plastic buckets – one of which contains the explosive material.
The huge animal raises its right leg to signal that he has found the tiny amount of TNT which is placed on a cotton swab.
In 2007, researchers discovered that an elephant herd in Angola, who were being tracked using GPS technology, purposely avoided landmine fields left over from the civil war – which had claimed the lives of many elephants.
When Chishuru was tasked with finding the TNT for the first time in over a year, he did so quickly without any refresher training.
“Elephants have a much better sense of smell than dogs do,” says Miller.
“We can say this primarily because they have more than double the amount of olfactory receptor genes in their DNA. Not only do elephants have a better sense of smell, but there is a lot less effort required in maintaining them as a biosensor.”
Michael Hensman, manager of Adventures with Elephants, said they initially set out to try and figure out how elephants were able to avoid those areas and it seems to be related to olfaction.
“We are never going to put elephants in to a dangerous situation like minefields where they could get hurt,” he says.
“The idea is to remotely collect samples and bring those samples out to the elephants for landmine area reduction.”
This research has been largely funded by the US Army Research Office. Researchers are also looking at other applications for the elephants, including cancer and diabetes screenings.
Diamonds used to “probe” ancient Earth
- Wits University
Diamonds dug up from ancient rock formations in the Johannesburg area, between 1890 and 1930 have revealed secrets of how ancient Earth worked.
Diamonds dug up from ancient rock formations in the Johannesburg area, between 1890 and 1930 – before the industrialisation of gold mining – have revealed secrets of how the Earth worked more than 3.5 billion years ago.
The three diamonds, which were extracted from the 3 billion-year-old Witwatersrand Supergroup – the rock formation that is host to the famous Johannesburg gold mines – were investigated by Dr. Katie Smart, Prof. Susan Webb and Prof. Lewis Ashwal from Wits University, Prof Sebastian Tappe from the University of Johannesburg, and Dr. Richard Stern from the University of Alberta (Edmonton, Canada), to study when modern-style plate tectonics began to operate on planet Earth. The diamonds were generously provided by Museum Africa, located in Johannesburg, with the assistance of curator Katherine James.
“Because diamonds are some of the the hardest, most robust material on Earth, they are perfect little time capsules and have the capacity to tell us what processes were occurring extremely early in Earth’s history,” says Dr Katie Smart, a Lecturer at the Wits School of Geoscience and the lead researcher on the paper, Early Archaean tectonics and mantle redox recorded in Witwatersrand diamonds, that was published in the journal, Nature Geoscience, in January.
Ancient history
The Earth is approximately 4.5 billion years old, and while a rock record exists from about 4 billion years ago, the complex preservational history of the most ancient rocks exposed on Earth’s surface has led to a heated debate amongst Geoscientists on when plate tectonics began operating on Earth. Many researchers believe plate tectonics began in the Archaean (the Eon that took place from 4 to 2.5 billion years ago), although the exact timing is highly contested.
While the diamonds of this study were found in 3 billion-year-old sedimentary rocks, diamond formation occurred much deeper, within Earth’s mantle. Additionally, based on the nitrogen characteristics of the diamonds, they also formed much earlier, around 3.5 billion years ago. Transport of the diamonds to the surface of the Earth by kimberlite-like volcanism, followed by their voyage across the ancient Earth surface and into the Witwatersrand basin, occurred between 3.5 and 3 billion years ago.
Probing the time capsules
By using an ion probe to analyse the carbon and nitrogen isotope compositions of the Witwatersrand diamonds, which have been pristinely preserved for more than three billion years, Smart and her team found that plate tectonics was likely in operation on Earth as early as 3.5 billion years ago.
“We can use the carbon and nitrogen isotope compositions of the diamonds to tell us where the source material involved in the formation of the Witwatersrand diamonds over 3 billion years ago came from,” says Smart.
“The nitrogen isotope composition of the Witwatersrand diamonds indicated a sedimentary source (nitrogen derived from the Earth’s surface) and this tells us that the nitrogen incorporated in the Witwatersrand diamonds did not come from the Earth’s mantle, but that it was rather transported from Earth’s surface into the upper mantle through plate tectonics. This is important because the nitrogen trapped in the Witwatersrand diamonds indicates that plate tectonics, as we recognise it today, was operating on ancient Archaean Earth, and actively transported material at Earth’s surface deep into the mantle.”
Earth as a planet is unique because of the dynamic process of plate tectonics that constantly transports surface material into the Earth’s mantle, which extends between 7 km to over 2800km below Earth’s surface. The process is driven by both convection cells within the Earth’s mantle and the character of crustal plates at Earth’s surface, where newly formed oceanic crustal plates are formed at spreading centres at mid-ocean ridges and then pushed apart. Older, cooler and more dense crust at convergent plate margins is then pulled into, or sinks, into the mantle at subduction zones. The subduction of crustal plates into the mantle can also carry sediments and organic material deep into the Earth’s interior.
Shaping the Earth
The plate tectonic process is vital for shaping the Earth as we know it, as the activity of plate tectonics causes earthquakes, volcanic eruptions, and is responsible for constructing Earth’s landscapes, such as deep sea trenches and building of mountains on the continents.
“Various researchers have tried to establish when exactly plate tectonics started on Earth, but while there are many investigations of ancient rocks on Earth’s surface – like the 3.5 billion year old Barberton Greenstone Belt here in South Africa, or the 4 billion year old Acasta Gneiss in northwest Canada – we are looking at the problem from a different viewpoint - by investigating minerals derived from Earth’s mantle,” says Smart.
“We are not the first research group to study diamonds in order to tell when plate tectonics began, but our study of confirmed Archaean diamonds has suggested that plate tectonics was in operation by at least 3.5 billion years.”
Solving unemployment in South Africa
- Wits University
Professor Boris Urban's goal is to create a new cadre of researchers in the field entrepreneurship.
Twenty years ago, the field of entrepreneurship was just a vague concept, only taught as a subject at MBAs around the country, but Professor Boris Urban, the Lamberti Chair in Entrepreneurship in the Wits Business School, has spent the last six years of his life establishing it as a dedicated field of research.
Being appointed as the first Chair in 2009, Urban believes that it is critical for South Africa to establish a business friendly environment wherein entrepreneurs can thrive.
“Entrepreneurship is one of the most important tools that we have to solve the unemployment problem in South Africa but to do this we need to create the right environment as well as an entrepreneurial mind-set for it to prosper,” he explains.
Our country, which is lagging behind our neighbours like Angola and Mozambique in creating citizens with a true entrepreneurial spirit, needs to create a critical mass of quality high-growth entrepreneurs to help root out unemployment and to create jobs. The only way to do this is through good education and legitimising entrepreneurship as a field of research. “The scholarly part is critical. Unless we have good education, we are never going to have a critical mass of entrepreneurs,” he says.
Urban’s research is interdisciplinary and juxtaposes commercial and social issues. To advance scholarship, his published works reflect a deep understanding of the multifaceted nature of entrepreneurial behaviour.
His primary research agenda is to integrate the personal and social foci of causation within a unified explanatory structure in order to understand entrepreneurial behaviour at the individual, organisational and societal levels.
“Hopefully through my efforts and my international collaborative projects, we are moving the field beyond just policy discourse. By adopting an evidence-based approach which follows the science-informed practice of entrepreneurship, we are building relevant African theory and models,” he elaborates.
His goal is to create a new cadre of researchers in the field in South Africa and to take entrepreneurship to the next level.
“I would like to elevate the field so that more nuanced and complex relationships in entrepreneurship are unveiled so as to identify differential typologies and impacts of entrepreneurial actions.”
While it is difficult to build an entrepreneurial ecosystem, Urban – who sits on various government and private sector advisory boards – believes that in time, an entrepreneurial culture can be cultivated in the country.
“It takes time, it takes realistic interventions, and it takes more than just building hype or setting up development agencies,” he says.
“It takes serious investment in human and social capital to increase the country’s total entrepreneurial quotient. Unless individuals feel that they are empowered with the relevant knowledge and skills required to create value – not only as entrepreneurs, but for established companies and society as a whole, we are never going to have a critical mass of entrepreneurs.”
Urban, an NRF-rated scientist, is a leading researcher and Professor in Entrepreneurship, has published more than 70 peer-reviewed academic journal articles, including in high-impact ISI and Financial Times top-ranked journals. He has also won a number of awards including the Research and Knowledge Exchange award from the UK-based Institute of Small Business and Entrepreneurship.
Analysing Zimbabwe’s brain drain
- Wits University
Why did many Zimbabweans leave their home country in search for work in SA?
Professor Miracle Benhura and Dr Prudence Magejo from the Wits School of Economic and Business Sciences are studying the returns on education in Zimbabwe using data from the 1995 and 2003 Zimbabwean Poverty Assessment Study Surveys in conjunction with the 1996 and 2001 South African Census data.
The main purpose of the study is to establish why many of their compatriots left Zimbabwe, their home country in search of work in South Africa.
“Zimbabwe suffered a substantial brain drain between 1995 and 2008 and we decided to look at the reasons why skilled workers were leaving the country,” says Magejo.
Benhura and Magejo studied about 10 000 documented Zimbabwean citizens, living in South Africa in 2001 and found that mainly prime-aged workers came to South Africa in search for work. They also found that highly qualified workers experienced the highest decline in returns on education during the Zimbabwean crisis.
The low reward for skills potentially explains the brain drain in Zimbabwe. Based on the results, one avenue to mitigate the problem would be to offer better returns on education,” adds Magejo.
After completing their PhDs at the University of Cape Town and University College Dublin in Ireland, respectively, Benhura and Magejo could not find well-incentivised jobs in Zimbabwe.
“Zimbabwe was already in a crisis when I finished my PhD in 2007 which pushed me to consider job offers in South Africa,” explains Benhura.
As labour and development economists, Benhura and Magejo are interested in determining whether Zimbabwe’s development policies in terms of politics, education and employment contributed to the country’s brain drain.
“Most literature on the subject is only anecdotal and we wanted to provide scientific evidence on the subject,” says Benhura.
As a separate research project, Benhura and Magejo are also studying South Africa’s labour unions and their role in the labour market.
“Unions are very strong in South Africa, compared to other African countries, so we looked at their contribution to inequality and also sought to identify the workers who benefit the most from union membership,” she adds.
They found that lower income workers benefited most from union membership, compared to their higher income counterparts. Further, they found that union membership confers better compensation on members compared to non-members.
“This union premium partly contributes to wage inequality in the South African labour market,” says Magejo.
Both Benhura and Magejo want to focus on issues of poverty and inequality in their future research. The plan is to broaden the scope to other African countries, since very little is known on the subject.
Cooling high-speed computers
- Wits University
The School of Mechanical, Industrial and Aeronautical Engineering is about to make headlines for the development of new technology to cool high-speed computers.
Under the leadership of Professor Ionel Botef, who recently set up Africa’s first Supersonic Spray Technology laboratory at Wits, the team has devised a micro heat sink for computers that could operate above 3GHz by using a process called cold spray technology.
The result is a porous copper micro heat sink that is 50 times smaller than those currently used and which could cool computers much more effectively. The research paper on the development of this technology by PhD student Agripa Hamweendo and Botef has led them to apply for a patent licence on the manufacturing process.
“We are currently busy with a paper for an ISI accredited journal but we are going to apply for a patent for the micro heat sink as a product itself too, before we submit the paper,” says Hamweendo.
“Postgraduate students have three other patents in the pipeline.”
The manufacturing process of the heat sink involves the cold spray technology, in which various powder materials are applied by bombarding the substrates at a high velocity of between 300 and 1 200 meters per second. The micro heat sink was created by spraying multiple layers of copper onto each other thereby creating multiple micro channels that serve as small ventilation shafts.
“The process can fabricate micro heat sinks with improved flow characteristics within micro channels, improved channel aspect ratios and multiple flow arrangements at the inlet and outlets,” explains Botef.
The cold spray process is highly versatile and can be used from the manufacturing of micro systems for electronics to the repair of large equipment such as the turbines in power stations.
Botef, who initially qualified as a mechanical engineer, is passionate about multidisciplinary studies and holds his PhD in Electrical and Information Engineering.
“That was the best decision that I have ever made as it gave me an opening into another world.”
When Botef first started out with the cold spray at Wits, he had to knock on the doors of his colleagues across campus to persuade them of the importance of the technology.
“Since then we have built an integrated Cold Spray and 3D Printing Laboratory and an academic team from various disciplines, including 37 postgraduate students from countries such as the Congo, Nigeria, Zambia, Zimbabwe and South Africa,” he adds.
Botef has worked in the aerospace industry with the likes of Rolls-Royce.
He is widely published in accredited journals and is internationally sought after for his specialist expertise. “Our mission is to build capable people who can act at the right time and who make critical decisions timeously to make a real difference in the world,” he concludes.
